Air cooler, intercooler and nuclear facility

ABSTRACT

A plurality of heat transfer pipes;
         a first header and a second header to which both ends of each of the heat transfer pipes that are disposed in parallel are fixed, respectively; a plurality of platy fins through which each of the heat transfer pipes is penetrated and that are provided at intervals in a direction in which the heat transfer pipes extend between the first header and the second header; and a fan that circulates an airflow between the platy fins are included. The first header and the second header are formed to be sectioned into multiple rows, the heat transfer pipes are disposed densely in an sectioned area of the first header and the second header, and the heat transfer pipes are disposed sparsely in an area between the sectioned areas of the first header and the second header.

FIELD

The present invention relates to an air cooler that cools heat transferpipes through which a medium circulates by using an airflow and to anintercooler and a nuclear facility to which the air cooler is used.

BACKGROUND

Conventionally, for example, the air cooler (fin tube type heatexchanger) according to Patent Document 1 consists of a large number ofplaty fins that are arranged in parallel at predetermined intervals andbetween which an airflow flows and heat transfer pipes that areperpendicularly inserted into the platy fins and in which a fluid flows.In the air cooler according to Patent Document 1, in order to improvethe heat transfer coefficient by reducing the dead water areas that arecaused in airflow backward areas with respect to the heat transferpipes, the pitch L1 between heat transfer pipes in the airflow directionwith respect to the outer diameter D of the heat transfer pipe (3 mm) isset at 1.2D≦L1≦1.8D and the pitch L2 between heat transfer pipes in thedirection orthogonal to the airflow with respect to the outer diameter Dof the heat transfer pipe is set at 2.6D≦L2≦3.5D.

CITATION LIST Patent Literature

Patent Literature 1: Japanese Laid-open Patent Publication No. 60-3188

SUMMARY Technical Problem

In order to achieve excellent heat exchange performance in the aircooler consisting of the large number of platy fins that are arranged inparallel at predetermined intervals and between which an airflow flowsand the heat transfer pipes that are perpendicularly inserted into theplaty fins and in which the fluid flows, it is preferable that the heattransfer pipes be disposed relatively densely and the pitches L1 and L2be set with respect to the outer diameter D of the heat transfer pipe todispose the heat transfer pipes in equilateral triangles. However, asfor welding both ends of the heat transfer pipes and fixing them toheaders at each of which multiple heat transfer pipes are assembled,disposing the heat transfer pipes densely makes welding difficult and,in contrast, increasing the pitch between equilateral triangles of theheat transfer pipes in consideration of assembling workability for, forexample, welding lowers the heat exchange performance.

The present invention is to solve the above-described problem and anobjective of the invention is to provide an air cooler, an intercooler,and a nuclear facility that make it possible to inhibit heat exchangeperformance from lowering and improve assembling workability.

Solution to Problem

According to an aspect of the present invention, an air cooler includes:a plurality of heat transfer pipes; headers to which both ends of eachof the heat transfer pipes that are disposed in parallel are fixed,respectively; a plurality of platy fins through which each of the heattransfer pipes is penetrated and that are provided at intervals in adirection in which the heat transfer pipes extend between the headers;and a fan that circulates an airflow between the platy fins, wherein theheaders are formed to be sectioned into multiple rows, the heat transferpipes are disposed densely in a sectioned area of the headers, and theheat transfer pipes are disposed sparsely in an area between thesectioned areas of the headers.

According to the air cooler, disposing the heat transfer pipes in thesectioned area of the headers makes it possible to inhibit the heatexchange performance from lowering, compared to the overall densestructure. Furthermore, disposing the heat transfer pipes 52C sparselyin the area between the headers that are sectioned makes it possible tosecure a gap between the heat transfer pipes for disposing, for example,a welding torch and thus improve assembling workability.

Advantageously, in the air cooler, the heat transfer pipes are disposedtriangularly, so that the heat transfer pipes are positioned differentlybetween a circulation direction in which the airflow is circulated bythe fan and a direction orthogonal to the circulation direction, theheat transfer pipes are disposed in equilateral triangles in thesectioned area of the headers, and the heat transfer pipes are disposedin isosceles triangles in the area between the sectioned areas of theheaders.

According to the air cooler, disposing the heat transfer pipes inequilateral triangles makes it possible to maintain heat exchangeperformance. Furthermore, disposing the heat transfer pipes in isoscelestriangles makes it possible to secure a gap for disposing, for example,a welding torch between the heat transfer pipes and thus improveassembling workability.

Advantageously, in the air cooler, a section boarders are disposed inthe headers in a direction intersecting with the direction in which theairflow is circulated by the fan.

Because the heat transfer pipes are disposed sparsely in the areabetween the headers that are sectioned, the interval between the heattransfer pipes increases along the section boarders. Here, when thedirection in which the airflow is circulated is along the sectionboarders, the airflow passes along the area having the increasedinterval between the heat transfer pipes, which tends to lower heatexchange efficiency. On the other hand, when the direction in which theairflow is circulated intersects with the section boarders, the airflowdoes not pass along the area having the increased interval between theheat transfer pipes, which tends to improve heat exchange efficiency.Accordingly, disposing the section boarders in the directionintersecting with the direction in which the airflow is circulated makesit possible to improve heat exchange efficiency.

Advantageously, in the air cooler, the platy fins are formed to bedivided into multiple blocks through each of which a predeterminednumber of the heat transfer pipes are penetrated, division endscorrespond to the positions of the section boarders in the headers, andthe division ends are provided to be against with each other.

Forming the platy fins to be divided into the multiple blocks througheach of which the predetermined number of the heat transfer pipes ispenetrated improves assembling workability. When the platy fins aredivided, dividing the platy fins according to the area where the pitchesbetween the heat transfer pipes are equal to each other leads to thesame structures of the blocks, which is preferable for construction.However, according to the first embodiment, because the heat transferpipes are disposed sparsely in the area between the headers that aresectioned, when the platy fins are divided according to the equalpitches between the heat transfer pipes, a gap occurs between thedivision ends of the blocks divided at the positions corresponding tothe section boarders, which may affect the performance. Accordingly,dividing the platy fins according to the area having equal pitchesbetween the heat transfer pipes, dividing the platy fins according tothe positions between the headers that are sectioned, and causing thedivision ends to be against with each other makes it possible tomaintain the heat exchange performance.

Advantageously, in the air cooler, the platy fins that are formed to bedivided into the blocks are further divided between the section boardersin the headers.

Further dividing the platy fins that are formed to be divided into theblocks further improves assembling workability.

According to an another aspect of the present invention, an intercoolerincludes a circulation piping for circulating cooling water for heatexchange using heat generated by a nuclear reactor of a nuclearfacility; and the air cooler according to any one of the claims 1 to 5that is provided to the circulation piping and that acquires the heat ofthe cooling water in the circulation piping through heat exchange.

According to the intercooler, it is possible to efficiently cools thecooling water in the nuclear facility.

Advantageously, in the intercooler, in the air cooler according to anyone of claims 1 to 5, a space in which the airflow circulates isprovided on a side where the fan takes in air and on an upstream sideaccording to the airflow with respect to the fan, and a plurality of theair coolers are disposed to be adjacent to each other, and the spaces ofthe air coolers communicate with each other.

According to the intercooler, the spaces on the upstream side accordingto the airflow with respect to the respective fans communicate with eachother, which makes it possible to inhibit the heat exchange performancefrom lowering.

According to an another aspect of the present invention, an intercoolerincludes a plurality of air coolers that are disposed to be adjacent toeach other and each of which comprises: a heat exchanger including aplurality of heat transfer pipes and headers to which both ends of eachof the heat transfer pipes that are disposed in parallel are fixed,respectively; a fan that circulates an airflow between the heat transferpipes; and a space in which the airflow circulates and that is providedon a side where the fan takes in air and on an upstream side accordingto the airflow with respect to the fan, wherein the spaces of the aircoolers communicate with each other.

According to the intercooler, the spaces on an upstream side of theairflow with respect to the respective fans communicate with each other,which makes it possible to inhibit the heat exchange performance fromlowering.

Advantageously, in the intercooler, the heat exchangers are provided onan upstream side according to the airflows with respect to the spaces.

According to the intercooler, the heat exchangers are disposed on theupstream side according to the airflows with respect to the spaces,which makes it possible to circulate the airflows preferable and thus toinhibit the heat exchange performance from lowering.

Advantageously, in the intercooler, the air cooler includes a pluralityof the heat exchangers.

According to the intercooler, each of the air coolers include the heatexchangers, which makes it possible to inhibit the heat exchangeperformance from lowering.

Advantageously, in the intercooler, at least part of the heat exchangersis set to be opposed to a direction in which the airflows circulatebetween the heat transfer pipes.

According to the intercooler, at least part of the heat exchangers isset to be opposed to the direction in which the airflow flows, whichmakes it possible to preferably circulate the airflows to inhibit theheat exchange performance from lowering.

Advantageously, in the intercooler, a partition is provided between theheat exchangers that are provided to be opposed to each other.

According to the intercooler, the partition is provided between the heatexchangers opposed to each other, which makes it possible to inhibit theheat exchange performance from lowering when, for example, a strong windoccurs.

Advantageously, in the intercooler, the header is formed to be sectionedinto multiple rows, and the heat transfer pipes are disposed densely ina sectioned area of the header and the heat transfer pipes are disposedsparsely in an area between the sectioned areas of the headers.

According to the intercooler, it is possible to inhibit the heatexchange performance from lowering.

According to an another aspect of the present invention, an intercoolerincludes a circulation piping for circulating cooling water for heatexchange using heat generated by a nuclear reactor of a nuclearfacility; and the intercooler that is provided to the circulation pipingand that acquires the heat of the cooling water in the circulationpiping through heat exchange.

According to the intercooler, it is possible to efficiently cool thecooling water in the nuclear facility.

According to an another aspect of the present invention, a nuclearfacility includes the air cooler; and the intercooler.

According to the nuclear facility, it is possible to cool the coolingwater in the nuclear facility efficiently.

Advantageous Effects of Invention

According to the present invention, it is possible to inhibit the heatexchange performance from lowering and improve assembling workability.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic configuration diagram schematically representing anuclear facility that includes an intercooler according to a firstembodiment of the present invention.

FIG. 2 is a schematic configuration diagram schematically representingan air cooler in the intercooler according to the first embodiment ofthe present invention.

FIG. 3 is a partially-omitted enlarged view of the air cooler accordingto the first embodiment of the present invention.

FIG. 4 is a diagram of the air cooler shown in FIG. 3 viewed in thedirection denoted by the arrow A.

FIG. 5 is a diagram of the air cooler shown in FIG. 3 viewed in thedirection denoted by the arrow A, representing a modification.

FIG. 6 is a diagram of the air cooler shown in FIG. 3 viewed in thedirection denoted by the arrow A, representing a modification.

FIG. 7 is a partially-omitted enlarged view of another air cooleraccording to the first embodiment of the present invention.

FIG. 8 is a schematic diagram showing an exemplary intercooler accordingto a second embodiment.

FIG. 9 is a front view showing the exemplary intercooler according tothe second embodiment.

FIG. 10 is a cross-sectional view of the intercooler according to thesecond embodiment, taken along the line A-A.

FIG. 11 is a cross-sectional view of the intercooler according to thesecond embodiment, taken along the line A-A.

FIG. 12 is a schematic diagram showing another exemplary intercooleraccording to the second embodiment.

FIG. 13 is a perspective view showing an intercooler according to athird embodiment.

FIG. 14 is a perspective view of an air cooler according to the thirdembodiment.

FIG. 15 is a front view of a heat exchanger according to the thirdembodiment.

FIG. 16 is a front view of the air cooler according to the thirdembodiment.

FIG. 17 is a cross-sectional view of the air cooler according to thethird embodiment, taken along the line B-B.

FIG. 18 is a side view of the intercooler according to the thirdembodiment.

FIG. 19 is a cross-sectional view of the intercooler according to thethird embodiment, taken along the line C-C.

FIG. 20 is a cross-sectional view of the intercooler according to thethird embodiment, taken along the line C-C.

FIG. 21 is a front view of an intercooler according to a modification.

FIG. 22 is a cross-sectional view of the air cooler according to themodification, taken along the line D-D.

DESCRIPTION OF EMBODIMENTS

Embodiments according to the present invention will be described indetail below according to the accompanying drawings. Note that theembodiments are not to be construed to limit the invention. Thecomponents of the following embodiments include ones that can be or areeasily replaced by those skilled in the art or ones that aresubstantially the same.

First Embodiment

FIG. 1 is a schematic configuration diagram schematically representing anuclear facility that includes an intercooler according to a firstembodiment. In the nuclear facility shown in FIG. 1, for example, apressurized water reactor (PWR) is used as a nuclear reactor 5. Anuclear facility 1 using the PWR nuclear reactor 5 consists of a primarycooling system 3 including the nuclear reactor 5 and a secondary coolingsystem 4 that exchanges heat with the primary cooling system 3. Aprimary cooling water serving as cooling water circulates in the primarycooling system 3 and a secondary cooling water serving as cooling watercirculates in the secondary cooling system 4.

The primary cooling system 3 includes the nuclear reactor 5 and a steamgenerator 7 that is connected to the nuclear reactor via a cooling waterpiping 6 a serving as a cold leg and a cooling water piping 6 b servingas a hot leg. The cooling water piping 6 b is provided with apressurizer 8. The cooling water piping 6 a is provided with a coolingwater pump 9. The nuclear reactor 5, the cooling water pipings 6 a and 6b, the steam generator 7, the pressurizer 8, and the cooling water pump9 are housed in a robust containment 10.

The nuclear reactor 5 is a PWR as described above and the inside of thenuclear reactor is filled with the primary cooling water. Inside thenuclear reactor 5, a large number of fuel assemblies 15 are housed and alarge number of control rods 16 are provided to be insertable into andextractable from the fuel assemblies 15. The control rods 16 are drivenby a control rod driver device 17 in a direction in which the controlrods 16 are inserted into and extracted from the fuel assemblies 15.When the control rod driver device 17 causes the control rods 16 to beinserted into the fuel assemblies 15, the burnup in the fuel assemblies15 is reduced and stops. On the other hand, when the control rod driverdevice 17 causes the control rods 16 to be extracted, the burnup in thefuel assemblies 15 is enhanced to the critical state. The control roddriver device 17 is configured to insert the control rods 16 into thefuel assemblies 15 when the power supply is terminated to a power lossstate.

When nuclear fission of the fuel assemblies 15 is caused by using thecontrol rods 16 while controlling the nuclear fission reaction, thenuclear fission generates thermal energy. The generated thermal energyheats the primary cooling water and the heated primary cooling water issent to the steam generator 7 via the cooling water piping 6 b. On theother hand, the primary cooling water that is sent from the steamgenerator 7 via the cooling water piping 6 a flows into the nuclearreactor 5 to cool the nuclear reactor 5.

The pressurizer 8 that is provided to the cooling water piping 6 bpressurizes the primary cooling water at high temperature, therebycontrolling boiling of the primary cooling water. The steam generator 7performs heat exchange between the primary cooling water at hightemperature and high pressure and the secondary cooling water toevaporate the secondary cooling water, thereby generating steam andcooling the primary cooling water at high temperature and high pressure.The cooling water pump 9 circulates the primary cooling water throughthe primary cooling system 3 and sends the primary cooling water fromthe steam generator 7 into the nuclear reactor 5 via the cooling waterpiping 6 a and sends the primary cooling water from the nuclear reactor5 via the cooling water piping 6 b to the steam generator 7. The diagramshows the mode where one steam generator 7 is provided to one nuclearreactor 5; however, multiple steam generators may be provided.

A set of operations in the primary cooling system 3 of the nuclearfacility 1 will be described here. When the primary cooling water isheated with the thermal energy generated by the nuclear fission reactionin the nuclear reactor 5, the heated primary cooling water is sent bythe cooling water pump 9 to the steam generator 7 via the cooling waterpiping 6 b serving as a hot leg. The primary cooling water at hightemperature that passes through the cooling water piping 6 b serving asa hot leg is pressurized by the pressurizer 8 to be inhibited fromboiling and, at a high-temperature and high-pressure state, flows intothe steam generator 7. The primary cooling water at high temperature andhigh pressure that have flown into the steam generator 7 is cooledthrough heat exchange with the secondary cooling water and the cooledprimary cooling water is sent by the cooling water pump 9 to the nuclearreactor 5 via the cooling water piping 6 a serving as a cold leg. Thecooled primary cooling water flows into the nuclear reactor 5, so thatthe nuclear reactor 5 is cooled. In other words, the primary coolingwater circulates between the nuclear reactor 5 and the steam generator7. The primary cooling water is light water that is used as a coolantand as a neutron moderator.

The secondary cooling system 4 includes a turbine 22 that is connectedto the steam generator 7 via a steam pipe 21, a condenser 23 that isconnected to the turbine 22, and a water supply pump 24 that is providedto a water supply pipe 26 connecting the condenser 23 and the steamgenerator 7. A generator 25 is connected to the turbine 22.

A set of operations in the secondary cooling system 4 of the nuclearfacility 1 will be described here. When the steam flows from the steamgenerator 7 via the steam pipe 21 into the turbine 22, the turbine 22rotates. Once the turbine 22 rotates, the generator 25 connected to theturbine 22 generates power. The steam that flows out of the turbine 22flows into the condenser 23. A cooling piping 27 is provided in thecondenser 23. A water intake piping 28 for supplying cooling water(e.g., sea water) is connected to one end of the cooling piping 27 and adischarge pipe 29 for discharging the cooling water to a drainage canalis connected to the other end of the cooling piping 27. In the condenser23, the steam flowing from the turbine 22 is cooled by the coolingpiping 27 to liquid. The secondary cooling water that returned to liquidis sent by the water supply pump 24 via the water supply pipe 26 to thesteam generator 7. Heat exchange between the secondary cooling watersent to the steam generator 7 and the primary cooling water is performedat the steam generator 7, so that the secondary cooling water returns tosteam again.

An intercooler 40 is connected to the secondary cooling system 4. Theintercooler 40 is a cooling system different from the above-describedflow in which the turbine 22 of the secondary cooling system 4 isrotated. The intercooler 40 is a sub cooling system that cools thesecondary cooling water in the secondary cooling system 4 when thecooling water cannot be cooled. Operations of the intercooler 40 arecontrolled by a controller 41.

The intercooler 40 includes a flow-in piping 42 and a flow-out piping 44that serve as a circulation piping that circulates cooling water(secondary cooling water) for heat exchange using the heat generated bythe nuclear reactor 5 of the nuclear facility 1, open/close valves 46and 48, a pump 49, and an air cooler 50. The flow-in piping 42 is apiping that guides the secondary cooling water in the liquid state(water) in the steam generator 7 to the air cooler 50. The flow-outpiping 44 is a piping that guides the secondary cooling water that iscooled by the air cooler 50 to the steam generator 7. The open/closevalve 46 is provided to the flow-in piping 42 to switch between openingand closing the flow-in piping 42. The open/close valve 46 is closed toinhibit the secondary cooling water in the steam generator 7 fromflowing into the air cooler 50 and is opened to allow the secondarycooling water in the steam generator 7 to flow into the air cooler 50.The open/close valve 48 is disposed in the flow-out piping 44 to switchbetween opening and closing the flow-out piping 44. The open/close valve48 is closed to inhibit the secondary cooling water in the air cooler 50from flowing into the steam generator 7 and is opened to allow thesecondary cooling water in the air cooler 50 to flow into the steamgenerator 7. The pump 49 is set in the flow-out piping 44. The pump 49sends the secondary cooling water in the flow-out piping 44 to the steamgenerator 7 to circulate the secondary cooling water flowing through theintercooler 40 between the intercooler 40 and the steam generator 7. Theair cooler 50 is an air-cooling cooler that sprays air to the secondarycooling water that is guided by the flow-in piping 42 to perform heatexchange between the air and the secondary cooling water, therebycooling the secondary cooling water. The structure of the air cooler 50will be described below.

In the intercooler 40, the open/close valves 46 and 48 are opened andthe pump 49 is driven by the controller 41 to circulate a medium servingas the secondary cooling water through the steam generator 7, theflow-in piping 42, the air cooler 50, the flow-out piping 44, and thesteam generator 7 according to the order they appear in this sentence.As described above, the flow-in piping 42, the flow-out piping 44, andthe air cooler 50 serve as a circulation path through which thesecondary cooling water in the steam generator 7 is circulated.Furthermore, in the intercooler 40, the circulating secondary coolingwater is cooled by the air cooler 50. Accordingly, the secondary coolingwater in the steam generator 7 can be cooled and the primary coolingwater can be kept cooled with the secondary cooling water.

Furthermore, an intercooler 90 is connected to the primary coolingsystem 3. The intercooler 90 is a cooling system different from theabove-described flow where heat exchange is performed by theabove-described steam generator 7 of the primary cooling system 3. Theintercooler 90 is a sub cooling system that cools the primary coolingwater in the primary cooling system 3 when the cooling water cannot becooled. Operations of the intercooler 90 are controlled by a controller91.

The intercooler 90 includes a flow-in piping 92 and a flow-out piping 94that serve as a circulation piping for circulating the cooling water(primary cooling water) for heat exchange by using the heat generated bythe nuclear reactor 5 of the nuclear facility 1, open/close valves 96and 98, a pump 99, and an air cooler 50. The flow-in piping 92 is apiping that is connected to a cooling water piping 6 a and that guidesthe primary cooling water supplied from the steam generator 7 to thenuclear reactor 5 to the air cooler 50. The flow-out piping 94 is apiping that is connected to the cooling water piping 6 b and that guidesthe primary cooling water that is cooled by the air cooler 50 to thesteam generator 7. The open/close valve 96 is disposed in the flow-inpiping 92 and switches between opening and closing the flow-in piping92. The open/close valve 96 is closed to inhibit the primary coolingwater from flowing into the air cooler 50 and is opened to allow theprimary cooling water to flow into the air cooler 5. The open/closevalve 98 is disposed in the flow-out piping 94 and switches betweenopening and closing the flow-out piping 94. The open/close valve 98 isclosed to inhibit the primary cooling water in the air cooler 50 fromflowing into the steam generator 7 and is opened to allow the primarycooling water in the air cooler 50 to flow into the steam generator 7.The pump 99 is set in the flow-out piping 94. The pump 99 sends theprimary cooling water in the flow-out piping 94 to the steam generator 7to circulate the primary cooling water flowing through the intercooler90 between the intercooler 90 and the steam generator 7. The air cooler50 is an air-cooling cooler that sprays air to the primary cooling waterthat is guided by the flow-in piping 92 to perform heat exchange betweenthe air and the primary cooling water, thereby cooling the primarycooling water. The structure of the air cooler 50 will be describedbelow.

In the intercooler 90, the open/close valves 96 and 98 are opened andthe pump 99 is driven by the controller 91 to circulate the secondarycooling water through the steam generator 7, the flow-in piping 92, theair cooler 50, the flow-out piping 94, and the steam generator 7according to the order they appear in this sentence. As described above,the flow-in piping 92, the flow-out piping 94, and the air cooler 50serve as a circulation path for circulating the primary cooling water inthe steam generator 7. Furthermore, in the intercooler 90, thecirculating primary cooling water is cooled by the air cooler 50.Accordingly, the primary cooling water in the steam generator 7 can becooled and the primary cooling water and the secondary cooling water canbe kept cooled. The controller 91 may be independent of theabove-described controller 41 of the intercooler 40 or the controller 41and the controller 91 may be a single controller.

The structure of the air cooler 50 will be described next. FIG. 2 is aschematic configuration diagram schematically representing the aircooler of the intercooler according to the first embodiment, FIG. 3 is apartially-omitted enlarged view of the air cooler according to the firstembodiment of the present invention, FIG. 4 is a diagram of the aircooler shown in FIG. 3 viewed in the direction denoted by the arrow A,FIG. 5 is a diagram of the air cooler shown in FIG. 3 viewed in thedirection denoted by the arrow A, representing a modification, and FIG.6 is a diagram of the air cooler shown in FIG. 3 viewed in the directiondenoted by the arrow A. As described above, the air cooler 50 isprovided to the intercooler 40 and the intercooler 90. The followingdescriptions will be on the intercooler 40 and the reference numerals onthe intercooler 90 will be represented with brackets.

As shown in FIG. 2, the air cooler 50 includes a fan 51 and a heatexchanger 52. The fan 51 and the heat exchanger 52 are supportedoutdoors by a frame (not shown) that is set on the ground or afoundation concrete that is provided on the ground.

The fan 51 is an axial fan or a suction fan. According to the firstembodiment, the heat exchanger 52 is disposed to be opposed to the fan51 and the fan 51 is provided between heat exchangers 52. The fan 51sends air upward from the bottom to send an airflow to each heatexchanger 52 that is opposed to the fan 51.

The heat exchanger 52 includes a first header 52A, a second header 52B,a heat transfer pipe 52C, and a platy fin 52D. The first header 52A is acontainer serving as a water chamber (header) that stores the coolingwater (the primary cooling water or the secondary cooling water) and thefirst header 52A is connected to the flow-in piping 42 (92) to supplythe cooling water flowing through the flow-in piping 42 (92). The secondheader 52B is a container serving as a water chamber (header) forstoring the cooling water and the second header 52B is connected to theflow-out piping 44 (94) to discharge the stored cooling water to theflow-out piping 44 (94). The heat transfer pipe 52C is provided toextend between the first header 52A and the second header 52B, and theends of the heat transfer pipe 52C are connected respectively to thefirst header 52A and the second header 52B. A plurality of heat transferpipes 52C are disposed in parallel. In other words, the cooling water(medium) that is supplied to the first header 52A is distributed fromthe first header 52A to flow into each of the heat transfer pipes 52Cand the heat transfer pipes 52C collectively send the cooling water tothe second header 52B. The platy fin 52D is formed to be like a thinplaty and is provided to be orthogonal to the direction in which each ofthe heat transfer pipes 52C extends, so that the heat transfer pipes 52Cpenetrate through the platy fin 52D. A plurality of platy fins 52D aredisposed at intervals along the direction in which each of the heattransfer pipes 52C extends. The heat exchanger 52 cools the coolingwater by causing heat exchange between the cooling water flowing in fromthe flow-in piping 42 (92) and the airflow guided by the fan 51 to coolthe cooling water.

In the heat exchanger 52 according to the first embodiment, the innerdiameter of the heat transfer pipe 52C is approximately 10 mm to 20 mmand the thickness of the platy fin 52D is approximately 0.2 mm to 0.5mm, and the pitch between the platy fins 52D is approximately 2 mm to 3mm. The heat transfer pipes 52C are formed of, for example, carbon steelor stainless steel. The platy fins 52D are formed of, for example,aluminum alloy or copper. The platy fins 52D are coated with, forexample, a resin material to prevent erosion.

As shown in FIGS. 3 and 4, the first header 52A and the second header52B are formed to be sectioned into multiple rows. Specifically,according to FIGS. 3 and 4, a plurality of partitions 52E that sectionthe inside of the first header 52A and the second header 52B intomultiple rows are provided. Sectioning the inside of the first header52A with the partitions 52E causes the cooling water to be distributedto each section on the side of the first header 52A and to be furtherdistributed from the sections to the heat transfer pipes 52C to permeatethe cooling water through each of the heat transfer pipes 52C, therebyimproving the heat exchange efficiency. On the other hand, sectioningthe inside of the second header 52B with the partitions 52E causes thecooling water in the sections to be collectively received on the side ofthe second header 52B and to be further discharged collectively from thesecond header 52B, thereby collecting the cooling water distributed atthe side of the first header 52A while reducing the pressure loss of thecooling water. The sections formed by the partitions 52E are formed toconverge at the position of the flow-in piping 42 (92) and the flow-outpiping 44 (94).

As shown in FIG. 4, the heat transfer pipes 52C are disposed densely inthe sectioned area of the first header 52A and the second header 52B,i.e., in the area between the provided partitions 52E, and are disposedsparsely in the area between the sectioned areas of the first header 52Aand second header 52B, i.e., in the area where the partition 52E ispositioned at the center.

Specifically, as shown in FIG. 4, the heat transfer pipes 52C aredisposed triangularly, so that the heat transfer pipes 52C arepositioned differently between a circulation direction W in which theairflow is circulated by the fan 51 and the direction orthogonal to thecirculation direction W. A pitch P₀ between the heat transfer pipes 52Cin the direction orthogonal to the circulation direction W serving asthe base of the triangular disposition has a relation with respect tothe outer diameter D of the heat transfer pipe 52C of 1.6≦P₀/D≦2.5. Inthe area between the provided partitions 52E, a pitch P₁ between theheat transfer pipes 52C in the circulation direction W has a relationwith respect to the outer diameter D of the heat transfer pipe 52C of1.6≦P₁/D≦2.5. In other words, in the area between the providedpartitions 52E, the heat transfer pipes 52C are disposed at the equalpitches P₀ and P₁ in the direction orthogonal to the circulationdirection W and in the circulation direction W. Preferably, the heattransfer pipes 52C are disposed in equilateral triangles. On the otherhand, in the area where the partition 52E is positioned at the center, apitch P₂ between the heat transfer pipes 52C in the circulationdirection W has a relation with respect to the outer diameter D of theheat transfer pipe 52C of 2.5≦P₂/D≦8. In other words, in the area wherethe partition 52E is positioned at the center, the heat transfer pipes52C are disposed at the pitches P₂ in the circulation direction W largerthan the pitch P₀ in the direction orthogonal to the circulationdirection W. In other words, the heat transfer pipes 52C are disposed inisosceles triangles.

As described above, the air cooler 50 according to the first embodimentincludes the heat transfer pipes 52C; the first header 52A and thesecond header 52B to which both ends of the heat transfer pipes 52C thatare disposed in parallel are fixed respectively; the platy fins 52Dthrough which each of the heat transfer pipes 52C is penetrated and thatare provided at intervals in the direction in which the heat transferpipes 52C extend between the first header 52A and the second header 52B;and the fan 51 that circulates the airflow between the platy fins 52D,wherein the partitions 52E that section the inside of the first header52A and the second header 52B into the multiple rows are provided, theheat transfer pipes 52C are disposed densely in the area between theprovided partitions 52E, and the heat transfer pipes 52C are disposedsparsely in the area where the partition 52E is positioned at thecenter.

According to the air cooler 50, disposing the heat transfer pipes 52Cdensely in the area between the provided partitions 52E makes itpossible to inhibit the heat exchange performance from lowering,compared to the overall dense structure (where, for example,1.6≦P₀/D≦2.5 and 1.6≦P₁/D≦2.5). Furthermore, disposing the heat transferpipes 52C sparsely in the area where the partition 52E is positioned atthe center makes it possible to secure a gap between the heat transferpipes 52C for disposing, for example, a welding torch and thus improveassembling workability.

For example, as shown in FIG. 4, in the area between the providedpartitions 52E, the pitches P₀ and P₁ between the heat transfer pipes52C in the direction orthogonal to the circulation direction W and inthe circulation direction W have relations with respect to the outerdiameter D of the heat transfer pipe 52C of 1.6≦P₀/D≦2.5 and1.6≦P₁/D≦2.5, respectively. Here, the heat exchange performance ismaintained at high level. On the other hand, in the area where thepartition 52E is positioned at the center, the pitch P₂ between the heattransfer pipes 52C in the circulation direction W has a relation withrespect to the outer diameter D of the heat transfer pipe 52C of2.5≦P₂/D≦8. Here, the heat exchange performance may lower, but a gap fordisposing, for example, a welding torch can be secured between the heattransfer pipes 52C, which improves assembling workability.

In the air cooler 50 according to the first embodiment, it is preferablethat the heat transfer pipes 52C be disposed triangularly, so that theheat transfer pipes 52C are positioned differently between thecirculation direction W in which the airflow is circulated by the fan 51and the direction orthogonal to the circulation direction W, be disposedin equilateral triangles in the area between the provided partitions52E, and be disposed in isosceles triangles in the area where thepartition 52E is positioned at the center.

According to the air cooler 50, disposing the heat transfer pipes 52C inequilateral triangles makes it possible to maintain heat exchangeperformance. Furthermore, disposing the heat transfer pipes 52C inisosceles triangles makes it possible to secure a gap for disposing, forexample, a welding torch between the heat transfer pipes 52C and thusimprove assembling workability.

In the air cooler 50 according to the first embodiment, as shown in FIG.4, it is preferable that the partitions 52E be disposed to extend in thedirection intersecting with the circulation direction W in which theairflow is circulated by the fan 51.

Because the heat transfer pipes 52C are disposed sparsely (2.5≦P₂/D≦4)in the area where the partition 52E is positioned at the center, theinterval between the heat transfer pipes 52C increases along thepartition 52E. Here, when the airflow circulation direction W is alongthe partition 52E, the airflow passes along the area having theincreased interval between the heat transfer pipes 52C, which tends tolower heat exchange efficiency. On the other hand, when the airflowcirculation direction W intersects with the direction in which thepartition 52E extends, the airflow does not pass along the area havingthe increased interval between the heat transfer pipes 52C, which tendsto improve heat exchange efficiency. Accordingly, disposing thepartitions 52E in the direction intersecting with the circulationdirection W in which the airflow is circulated by the fan 51 makes itpossible to improve heat exchange efficiency. In order to achieve aneffect of improving heat exchange efficiency significantly, it ispreferable to dispose the partitions 52E to extend in the directionorthogonal to the circulation direction W in which the airflow iscirculated by the fan 51.

Furthermore, in the air cooler 50 according to the first embodiment, itis preferable as shown in FIG. 5 that the platy fin 52D be formed to bedivided into multiple blocks 52Da through each of which a predeterminednumber of heat transfer pipes 52C are penetrated and, when viewed in thedirection in which the heat transfer pipes 52C extend, division ends52Db correspond to the positions in which the partitions 52E areprovided and the division ends be provided to be against with eachother.

Forming the platy fins 52C to be divided into the blocks 52Da througheach of which a predetermined number of heat transfer pipes 52C ispenetrated improves assembling workability. When the platy fins 52D aredivided, dividing the platy fins 52D according to the area where thepitches between the heat transfer pipes 52C are equal to each other(which means that the pitches P₀ and P₁ between the heat transfer pipes52C in the direction orthogonal to the circulation direction W and inthe circulation direction W have relations with respect to the outerdiameter D of the heat transfer pipe 52C of 1.6≦P₀/D≦2.5 and1.6≦P₁/D≦2.5) leads to the same structures of the blocks 52Da, which ispreferable for construction. However, according to the first embodiment,because the heat transfer pipes 52C are disposed sparsely in the areawhere the partition 52E is positioned at the center, when the platy fins52D are divided according to the equal pitches between the heat transferpipes 52C, a gap occurs between the division ends 52Db of the blocks52Da divided at the positions corresponding to the partitions 52E, whichmay affect the performance. For example, when there is a shortage in theheat transfer area, the heat transfer area can be increased by dividingthe platy fins 52D according to the area having equal pitches betweenthe heat transfer pipes 52C, by dividing the platy fins 52D according tothe positions in which the partitions 52E are provided, and by causingthe division ends 52Db to be against with each other. In the area wherethe division ends 52Db are against with each other, the division ends52Db may be against with each other in a convex and concave manner ormay be superimposed with each other on a slope to be against with eachother to adjust the performance.

In the air cooler 50 according to the first embodiment, as shown in FIG.6, when viewed in the direction in which the heat transfer pipes 52Cextend, it is preferable that the platy fins 52D that are formed to bedivided into the blocks 52Da according to FIG. 5 be further dividedbetween the areas in each of which the partition 52E is provided,(between section boarders in the first header 52A and the second header52B), into a plurality of small blocks 52Daa.

Because the platy fins 52D that are formed to be divided into the blocks52Da are further divided, the assembling workability further improves.When the platy fins 52D that are formed to be divided into the blocks52Da are further divided, it is preferable that, as shown in FIG. 6, theplaty fins 52D be divided according to each row of the heat transferpipe 52C (here per row) parallel to division of the blocks 52Da, becausethe further divided small blocks 52Daa include approximately the samestructures.

Furthermore, the intercooler 40 (90) according to the first embodimentincludes the flow-in piping 42 (92) and the flow-out piping 44 (94) thatserve as the circulation piping for circulating the cooling water (theprimary cooling water or the secondary cooling water) for heat exchangeusing the heat generated by the nuclear reactor 5 of the nuclearfacility 1 and the above-described air cooler 50 that is provided to thecirculation piping and that acquires the heat of the cooling water inthe circulation piping through heat exchange.

According to the intercooler 40 (90), it is possible to efficiently coolthe cooling water in the nuclear facility 1.

FIG. 7 is a partially-omitted enlarged view of another air cooleraccording to the first embodiment of the present invention. As describedabove, the air cooler 50 is provided to the intercooler 40 and theintercooler 90. The following descriptions are on the intercooler 40 andthe reference numerals on the intercooler 90 will be represented withbrackets.

The air cooler shown in FIG. 7 is different from the air cooler 50 shownin FIG. 2 in the configuration of the heat exchanger 52 and isequivalent to the air cooler 50 in the fan 51.

As shown in FIG. 7, the heat exchanger 52 includes the first header 52A,the second header 52B, the heat transfer pipes 52C, and the platy fins52D. The first header 52A and the second header 52B are containersserving as water chambers (headers) that store the cooling water (aprimary cooling water and a secondary cooling water) and are connectedto the flow-out piping 44 (94) to discharge the stored cooling water tothe flow-out piping 44 (94) while being connected to the flow-in piping42(92) to supply the cooling water flowing through the flow-in piping 42(92). The heat transfer pipe 52C is provided to extend between the firstheader 52A and the second header 52B and the ends of the heat transferpipe 52C is connected to the first header 52A and the second header 52Brespectively. The heat transfer pipe 52C is provided to extend betweenthe first header 52A and the second header 52B, and the ends of the heattransfer pipe 52C are connected respectively to the first header 52A andthe second header 52B. A plurality of heat transfer pipes 52C aredisposed in parallel. The platy fin 52D is formed to be like a thinplate and is provided orthogonally to the direction in which each heattransfer pipe 52C extends, so that the heat transfer pipes 52C penetratethrough each platy fin 52D. A plurality of platy fins 52D are disposedat intervals along the direction in which each heat transfer pipe 52Cextend. The heat exchanger 52 cools the cooling water by causing heatexchange between the cooling water flowing in from the flow-in piping 42(92) and the airflow that is guided by the fan 51.

In the heat exchanger 52 according to the first embodiment shown in FIG.7, the inner diameter of the heat transfer pipe 52C is approximately 10mm to 20 mm and the thickness of the platy fin 52D is approximately 0.2mm to 0.5 mm, and the pitch between the platy fins 52D is approximately2 mm to 3 mm. The heat transfer pipes 52C are formed of, for example,carbon steel or stainless steel. The platy fins 52D are formed ofaluminum alloy or copper. The platy fins 52D are coated with a resinmaterial to prevent erosion.

As shown in FIG. 7, the first header 52A and the second header 52B areformed to be sectioned into multiple rows. Specifically, the firstheader 52A and the second header 52B are formed to be divided. Accordingto FIG. 7, the first header 52A is formed to be divided into four rowsof first division headers 52Aa, 52Ab, 52Ac and 52Ad. The second header52B is formed to be divided into four rows of second division headers52Ba, 52Bb, 52Bc and 52Bd. The first division header 52Aa and the seconddivision header 52Ba are disposed to be opposed to each other and areconnected with the heat transfer pipes 52C. The first division header52Ab and the second division header 52Bb are disposed to be opposed toeach other and are connected with the heat transfer pipes 52C. The firstdivision header 52Ac and the second division header 52Bc are disposed tobe opposed to each other and are connected with the heat transfer pipes52C. The first division header 52Ad and the second division header 52Bdare disposed to be opposed to each other and are connected with the heattransfer pipes 52C. Furthermore, the flow-in piping 42 (92) is connectedto the first division header 52Aa and the flow-out piping 44 (94) isconnected to the first division header 52Ad. Furthermore, the firstdivision header 52Ab and the first division header 52Ac are connected toeach other via a connection pipe 52F, the second division header 52Baand the second division header 52Bb are connected to each other via aconnection pipe 52F, and the second division header 52Bc and the seconddivision header 52Bd are connected to each other via a connection pipe52F. Accordingly, the cooling water supplied from the flow-in piping 42(92) is sent from the first division header 52Aa to the second divisionheader 52Ba via the heat transfer pipes 52C, is sent from the seconddivision header 52Ba to the second division header 52Bb via theconnection pipe 52F, is sent from the second division header 52Bb to thefirst division header 52Ab via the heat transfer pipes 52C, is sent fromthe first division header 52Ab to the first division header 52Ac via theconnection pipe 52F, is sent from the first division header 52Ac to thesecond division header 52Bc via the heat transfer pipes 52C, is sentfrom the second division header 52Bc to the second division header 52Bdvia the connection pipe 52F, is sent from the second division header52Bd to the first division header 52Ad via the heat transfer pipes 52C,and is discharged to the flow-out piping 44 (94). As described above,each of the first header 52A and the second header 52B is formed to bedivided into multiple rows to distribute the cooling water to eachheader and further distribute the cooling water to the heat transferpipes 52C to allow the cooling water to permeate through each of theheat transfer pipes 52C, which makes it possible to improve the heatexchange efficiency. There is no limitation on the number of rows intowhich the first header 52A and the second header 52B are divided.

The heat transfer pipes 52C are disposed densely in the sectioned areaof the first header 52A and the second header 52B, i.e., in the area ofthe divided division header, and are disposed sparsely in the areabetween the sectioned areas of the first header 52A and the secondheader 52B, i.e., in the area between adjacent division headers. In thisstructure, it does not matter whether to provide gaps between the firstdivision headers 52Aa, 52Ab, 52Ac and 52Ad and the second divisionheaders 52Ba, 52Bb, 52Bc and 52Bd. For example, when gaps are provided,it is assumed that gaps corresponding to the thickness of the partition52E may be provided. When no gap is provided, it may be assumed that thethickness of the adjacent division headers is increased by the thicknessof the partition 52E shown in FIG. 4.

As can be seen with reference to FIG. 4, the heat transfer pipes 52C aredisposed triangularly, so that the heat transfer pipes 52C arepositioned differently between the circulation direction W in which anairflow is circulated by the fan 51 and the direction orthogonal to thecirculation direction W. A pitch P₀ between the heat transfer pipes 52Cin the direction orthogonal to the circulation direction W serving asthe base of the triangular disposition has a relation with respect tothe outer diameter D of the heat transfer pipe 52C of 1.6≦P₀/D≦2.5. Inthe area of the divided division header, a pitch P₁ between the heattransfer pipes 52C in the circulation direction W has a relation withrespect to the outer diameter D of the heat transfer pipe 52C of1.6≦P₁/D≦2.5. In other words, In the area of the divided divisionheader, the heat transfer pipes 52C are disposed at the equal pitches P₀and P₁ in the direction orthogonal to the circulation direction W and inthe circulation direction W. Preferably, the heat transfer pipes 52C aredisposed in equilateral triangles. On the other hand, in the areabetween adjacent division headers, a pitch P₂ between the heat transferpipes 52C in the circulation direction W has a relation with respect tothe outer diameter D of the heat transfer pipe 52C of 2.5≦P₂/D≦8. Inother words, in the area between adjacent division headers, the heattransfer pipes 52C are disposed at the pitches P₂ in the circulationdirection W larger than the pitch P₀ in the direction orthogonal to thecirculation direction W. In other words, the heat transfer pipes 52C aredisposed in isosceles triangles.

In the heat exchanger 52 shown in FIG. 7, it is preferable that theairflow caused by the fan 51 be in the circulation direction W from theside of the flow-out piping 44 (94) toward the flow-in piping 42(92).Sending the airflow from the downstream side at a low temperature ofdischarge from the heat exchanger 52 via the heat transfer pipes 52Cmakes it possible to increase the volume of heat exchange, whichimproves heat exchange performance.

As described above, the air cooler 50 according to the first embodimentshown in FIG. 7 includes the heat transfer pipes 52C; the first header52A and the second header 52B to which both ends of each of the heattransfer pipes 52C that are disposed in parallel are fixed respectively;the platy fins 52D through which each of the heat transfer pipes 52C ispenetrated and that are provided at intervals in the direction in whichthe heat transfer pipes 52C extend between the first header 52A and thesecond header 52B; and the fan 51 that circulates the airflow betweenthe platy fins 52D, wherein the first header 52A and the second header52B are formed to be sectioned into the multiple rows, the heat transferpipes 52C are disposed densely in the sectioned area of the first header52A and the second header 52B, and the heat transfer pipes 52C aredisposed sparsely in the area between the sectioned areas of the firstheader 52A and second header 52B.

According to the air cooler 50, compared to the overall dense structure(where, for example, 1.6≦P₀/D≦2.5 and 1.6≦P₁/D≦2.5), disposing the heattransfer pipes 52C densely in the sectioned area of the first header 52Aand the second header 52B makes it possible to inhibit the heat exchangeperformance from lowering. Furthermore, disposing the heat transferpipes 52C sparsely in the area between the sectioned areas of the firstheader 52A and second header 52B makes it possible to secure a gapbetween the heat transfer pipes 52C for disposing, for example, awelding torch and thus improve assembling workability.

For example, as can be seen with reference to FIG. 4, in the sectionedarea of the first header 52A and the second header 52B, the pitches P₀and P₁ between the heat transfer pipes 52C in the direction orthogonalto the circulation direction W and in the circulation direction W haverelations with respect to the outer diameter D of the heat transfer pipe52C of 1.6≦P₀/D≦2.5 and 1.6≦P₁/D≦2.5. Here, the heat exchangeperformance is maintained at high level. On the other hand, in the areabetween the sectioned areas of the first header 52A and second header52B, the pitch P₂ between the heat transfer pipes 52C in the circulationdirection W has a relation with respect to the outer diameter D of theheat transfer pipe 52C of 2.5≦P₂/D≦8. Here, the heat exchangeperformance may lower, but a gap for disposing, for example, a weldingtorch can be secured between the heat transfer pipes 52C, which improvesassembling workability.

In the air cooler 50 according to the first embodiment shown in FIG. 7,it is preferable that the heat transfer pipes 52C be disposedtriangularly, so that the heat transfer pipes 52C are positioneddifferently between the circulation direction W in which the airflow iscirculated by the fan 51 and the direction orthogonal to the circulationdirection W, be disposed in equilateral triangles in the sectioned areaof the first header 52A and the second header 52B, and be disposed inisosceles triangles in the area between the sectioned areas of the firstheader 52A and second header 52.

According to the air cooler 50, disposing the heat transfer pipes 52C inequilateral triangles makes it possible to maintain heat exchangeperformance. Furthermore, disposing the heat transfer pipes 52C inisosceles triangles makes it possible to secure a gap for disposing, forexample, a welding torch between the heat transfer pipes 52C and thusimprove assembling workability.

In the air cooler 50 according to the first embodiment shown in FIG. 7,it is preferable with reference to FIG. 4 that, in the first header 52Aand the second header 52B, the section boarders divided in the directionintersecting with the circulation direction W in which the airflow iscirculated by the fan 51 be disposed. The section boarders referred toherein correspond to the positions of the partitions 52E shown in FIG.4.

Because the heat transfer pipes 52C are disposed sparsely (2.5≦P₂/D≦4)in the area between the sectioned areas of the first header 52A and thesecond header 52B, the interval between the heat transfer pipes 52Cincreases along the divided section boarder. Here, when the airflowcirculation direction W is along the section boarder, the airflow passesalong the area having the increased interval between the heat transferpipes 52C, which tends to lower heat exchange efficiency. On the otherhand, when the airflow circulation direction W intersects with thedirection in which the section boarder extends, the airflow does notpass along the area having the increased interval between the heattransfer pipes 52C, which tends to improve heat exchange efficiency.Accordingly, disposing the divided section boarders in the directionintersecting with the circulation direction W in which airflow iscirculated by the fan 51 makes it possible to improve heat exchangeefficiency. In order to achieve an effect of improving heat exchangeefficiency significantly, it is preferable to dispose the dividedsection boarders to extend in the direction orthogonal to thecirculation direction W in which the airflow is circulated by the fan51.

Furthermore, in the air cooler 50 according to the first embodimentshown in FIG. 7, as can be seen with reference to FIG. 7, it ispreferable that the platy fin 52D be formed to be divided into multipleblocks 52Da through each of which a predetermined number of heattransfer pipes 52C is penetrated and, when viewed in the direction inwhich the heat transfer pipes 52C extend, division ends 52Db correspondto the positions of the section boarders in the first header 52A and thesecond header 52B and the division ends 52Db be provided to be againstwith each other. The positions of the section boarders in the firstheader 52A and the second header 52B referred herein correspond to thepositions of the partitions 52E shown in FIG. 5.

Forming the platy fins 52C to be divided into the blocks 52Da througheach of which a predetermined number of heat transfer pipes 52C ispenetrated improves assembling workability. When the platy fins 52D aredivided, dividing the platy fins 52D according to the area where thepitches between the heat transfer pipes 52C are equal to each other(which means that the pitches P₀ and P₁ between the heat transfer pipes52C in the direction orthogonal to the circulation direction W and inthe circulation direction W have relations with respect to the outerdiameter D of the heat transfer pipe 52C of 1.6≦P₀/D≦2.5 and1.6≦P₁/D≦2.5) leads to the same structures of the blocks 52Da, which ispreferable for construction. However, according to the first embodiment,because the heat transfer pipes 52C are disposed sparsely in the areabetween the sectioned areas of the first header 52A and the secondheader 52B, when the platy fins 52D are divided according to the equalpitches between the heat transfer pipes 52C, a gap occurs between thedivision ends 52Db of the blocks 52Da divided at the positions of thesection boarders in the first header 52A and the second header 52B,which may affect the performance. For example, when there is a shortagein the heat transfer area, the heat transfer area can be increased bydividing the platy fins 52D according to the area having equal pitchesbetween the heat transfer pipes 52C, by dividing the platy fins 52Daccording to the positions of the section boarders in the first header52A and the second header 52B, and by causing the division ends 52Db tobe against with each other. In the area where the division ends 52Db areagainst with each other, the division ends 52Db may be against with eachother in a convex and concave manner or may be superimposed with eachother on a slope to be against with each other to adjust theperformance.

In the air cooler 50 according to the first embodiment shown in FIG. 7,as can be seen with reference to FIG. 6, when viewed in the direction inwhich the heat transfer pipes 52C extend, it is preferable that theplaty fins 52D that are formed to be divided into the blocks 52Daaccording to FIG. 5 be further divided between the section boarders inthe first header 52A and the second header 52B into a plurality of smallblocks 52Daa. The positions of the section boarders in the first header52A and the second header 52B correspond to the positions of thepartitions 52E shown in FIG. 6.

Because the platy fins 52D that are formed to be divided into the blocks52Da are further divided, the assembling workability further improves.When the platy fins 52D that are formed to be divided into the blocks52Da are further divided, it is preferable that, as can be seen withreference FIG. 6, the platy fins 52D be divided according to each row ofthe heat transfer pipe 52C (here per row) parallel to division of theblocks 52Da, because the further divided small blocks 52Daa includeapproximately the same structures.

Second Embodiment

A second embodiment of the present invention will be described nextaccording to the drawings. FIG. 8 is a schematic diagram showing anexemplary intercooler 40 a according to the second embodiment. FIG. 9 isa front view showing the exemplary intercooler 40 a according to thesecond embodiment. FIG. 10 is a cross-sectional view of the intercooler40 a according to the second embodiment, taken along the line A-A. FIG.11 is a cross-sectional view of the intercooler 40 a according to thesecond embodiment, taken along the line A-A. The intercooler 40 aaccording to the second embodiment is different from the intercooler 40according to the first embodiment in that the intercooler 40 a includesa plurality of air cooler 50 a and 50 b and a space 104 on the upstreamsides according to airflows with respect to fans 51 a and 51 b. Becauseother aspects of the structure are the same as those of the firstembodiment, descriptions thereof will be omitted.

As shown in FIG. 8, the intercooler 40 a according to the secondembodiment includes a first air cooler 50 a, a second air cooler 50 b,and a cover 102 having a space 104 internally. The first air cooler 50 aand the second air cooler 50 b have the same structure as that of theair cooler 50 according to the first embodiment. The cover 102 is, forexample, a frame member. As shown in FIG. 10, the cover 102 is connectedto the first air cooler 50 a at one end 107 and is connected to thesecond air cooler 50 b at another end 108. In other words, theintercooler 40 a is manufactured such that the first air cooler 50 a andthe second air cooler 50 b are adjacent to each other via the cover 102.An air inlet 106 is formed on a side surface of the cover 102.

As shown in FIG. 10, the fan 51 a of the first air cooler 50 a and thefan 51 b of the second air cooler 50 b are housed in the space 104 inthe cover 102. The fan 51 a causes an airflow Wx toward a heat exchanger52 a of the first air cooler 50 a and the fan 51 b causes an airflow Wxtoward a heat exchanger 52 b of the second air cooler 50 b. The area onthe side where the air from the fan 51 a is taken and on the upstreamside according to the airflow Wx with respect to the fan 51 a is thespace 104. Similarly, the area on the side where the air from the fan 51b is taken and on the upstream side according to the airflow Wx withrespect to the fan 51 b is the space 104. In other words, the fans 51 aand 51 b share the area on the upstream sides according to the airflowsWx and the spaces on the upstream sides according to the airflows Wxwith respect to the fans 51 a and 51 b communicate with each other.Furthermore, according to the second embodiment, the heat exchanger 52 aand 52 b are respectively positioned on downstream sides according tothe airflows Wx with respect to the fans 51 a and 51 b. A cooling methodtaken by the intercooler 40 a will be described next.

The fans 51 a and 51 b are driven by, for example, the controller 41.FIG. 10 shows the case where both of the fan 51 a and the fan 51 b aredriven. As shown in FIG. 10, when both of the fans 51 a and 51 b aredriven, the fan 51 a causes an airflow Wx from the air inlet 106 towardthe heat exchanger 52 a. Similarly, the fan 51 b causes an airflow Wxfrom the air inlet 106 toward the heat exchanger 52 b. The airflows Wxpasses through heat transfer pipes 52 aC and heat transfer pipes 52 bCto cool the cooling water in the heat transfer pipes 52 aC and thecooling water in the heat transfer pipes 52 bC and flow out to theoutside of the intercooler 40 a. The case where only the fan 51 a isdriven will be described next.

FIG. 11 shows the case where only the fan 51 a is driven. As shown inFIG. 11, when only the fan 51 a is driven, the fan 51 a causes anairflow Wx from the air inlet 106 toward the heat exchanger 52 a to coolthe cooling water in the heat exchanger 52 a. Because the fan 51 b isnot driven, the fan 51 b does not cause any airflow from the air inlet106 toward the heat exchanger 52 b. However, the area on the upstreamside according to the airflow with respect to the fan 51 b and the areaon the upstream side according to airflow with respect to the fan 51 ashare the space 104. Accordingly, the fan 51 a causes an airflow Wy fromthe heat exchanger 52 b toward the fan 51 a. The airflow Wy passesbetween the heat transfer pipes 52 bC from the outside of theintercooler 40 a and merges with the airflow Wx. The airflow Wy passesbetween the heat transfer pipes 52 bC, thereby cooling the cooling waterin the heat transfer pipes 52 bC.

As described above, in the intercooler 40 a according to the secondembedment, the areas on the upstream sides with respect to the fans 51 aand 51 b communicate with each other in the space 104. Accordingly, onlydriving one of the fans makes it possible to generate airflows towardboth of the heat exchangers 52 a and 52 b to cool the cooling water inthe heat exchangers 52 a and 52 b. For example, when the controller 41is driven by using an emergency power supply in an emergency, it isdesirable to reduce the power usage of emergency power supply as much aspossible. In this case, the intercooler 40 a according to the secondembodiment makes it possible to cool the cooling water in a plurality ofheat exchangers by driving only one of the fans to reduce power usage.Accordingly, the intercooler 40 a according to the second embodimentmakes it possible to inhibit the heat exchange performance from loweringwhile reducing the power usage. The intercooler 40 a according to thesecond embodiment includes a plurality of air coolers. Accordingly, whenmaintenance is required for an air cooler, part of the air coolers canbe detached from the intercooler 40 a for maintenance. Accordingly, formaintenance of an air cooler, because the intercooler 40 a is capable ofcooling the cooling water depending on another air cooler, the coolingfunction is not lost. According to the second embodiment, theintercooler 40 a includes two air coolers. Alternatively, the airintercooler 40 a may include three or more air coolers.

FIG. 12 is a schematic diagram showing another exemplary intercooleraccording to the second embodiment. The intercooler 40 a is not limitedto the setting layout represented according to the second embodiment.According to the second embodiment, the heat exchangers 52 a and 52 bare positioned on the downstream sides according to the airflow Wx withrespect to the respective fans 51 a and 51 b; however, the positions arenot limited to this. For example, as shown in FIG. 12, an intercooler 40b may be one in which heat exchangers are positioned on the upstreamside according to airflow with respect to fans and suction fans are usedfor the fans. As shown in FIG. 12, a fan 51 ao of a first air cooler 50ao and a fan 51 bo of a second air cooler 50 bo are suction fans. Thefan 51 ao causes an airflow Wxo from a heat exchanger 52 ao toward theoutside of a cover 102 o. When the fan 51 bo is not driven and only thefan 51 ao is driven, the fan 51 ao causes an airflow Wyo in addition tothe airflow Wxo. The airflow Wyo is an airflow from a heat exchanger 52bo of the second air cooler 50 bo toward the fan 51 ao and the airflowWyo cools the cooling water in the heat exchanger 52 bo. In the caseshown in FIG. 12, because the heat exchangers 52 ao and 52 bo are cooledby the external air, the cooling water can be cooled more efficiently.As described above, in the intercooler 40 a, when a plurality of aircoolers 50 according to the first embodiment are set adjacently and thespaces on the upstream sides with respect to the fans 51 communicatewith each other, it is possible to inhibit the heat exchange performancefrom lowering while reducing the power usage.

Third Embodiment

A third embodiment of the present invention will be described next withreference to the drawings. FIG. 13 is a perspective view showing anintercooler 40 s according to the third embodiment. The intercooler 40 saccording to the third embodiment is different from the secondembodiment in that a plurality of air coolers each including a fan and aplurality of heat exchangers are disposed adjacently. Descriptions willbe omitted for components of the intercooler 40 s according to the thirdembodiment having the same structures as those of the second embodiment.

As shown in FIG. 13, the intercooler 40 s according to the thirdembodiment includes a first air cooler 50 sa, a second air cooler 50 sb,and a third air cooler 50 sc. Although specifically described below, thefirst air cooler 50 sa, the second air cooler 50 sb, and the third aircooler 50 sc are disposed adjacently in the intercooler 40 s accordingto the third embodiment.

FIG. 14 is a perspective view of the first air cooler 50 sa according tothe third embodiment. As shown in FIG. 14, the first air cooler 50 saincludes a cover 110 a, heat exchangers 52 sa 1, 52 sa 2, 52 sa 3, 52 sa4, 52 sa 5, 52 sa 6 and a fan 51 sa (hereinafter, the heat exchangers 52sa 1 to 52 sa 6 will be described as heat exchangers 52 sa when they arenot required to be distinguished from one another).

The cover 110 a includes a rectangular plate 112 a and legs 114 a thatextend from the respective corners of the plate 112 a in a directionintersecting with the plane parallel to the plate 112 a. Althoughspecifically described below, the heat exchangers 52 sa are inside thecover 110 a and are disposed in the space surrounded by the plate 112 aand the legs 114 a. The fan 51 sa is provided to the plate 112 a.

The fan 51 sa is, for example, an axial fan that axially intakes anddischarges an airflow. An axial fan is capable of causing high-pressureairflows and thus cooling the cooling water preferably. The fan 51 sais, however, not limited to axial fan as long as airflows can be caused.The fan 51 sa is driven by, for example, the controller 41.

FIG. 15 is a front view of the heat exchanger 52 sa according to thethird embodiment. As shown in FIG. 15, the heat exchanger 52 sa includesa first header 52 sA, a second header 52 sB, a plurality of heattransfer pipes 52 sC, and a plurality of platy fin 52 sD. The firstheader 52 sA is a container serving as a water chamber (header) thatstores the cooling water (the primary cooling water or the secondarycooling water) and the first header 52 sA is connected to the flow-inpiping 42 (92) to supply the cooling water flowing through the flow-inpiping 42 (92). The second header 52 sB is a container serving as awater chamber (header) for storing the cooling water and the secondheader 52 sB is connected to the flow-out piping 44 (94) to dischargethe stored cooling water to the flow-out piping 44 (94).

The heat transfer pipe 52 sC is provided to extend between the firstheader 52 sA and the second header 52 sB, and the ends of the heattransfer pipe 52 sC are connected respectively to the first header 52 sAand the second header 52 sB. A plurality of heat transfer pipes 52 sCare disposed in parallel. In other words, the cooling water (medium)that is supplied to the first header 52 sA is distributed from the firstheader 52 sA and flows into each of the heat transfer pipes 52 sC andthe heat transfer pipes 52 sC collectively send the cooling water to thesecond header 52 sB.

The platy fin 52 sD is formed to be like a thin plate and is providedorthogonally to the direction in which each of the heat transfer pipes52C extends, so that each of the heat transfer pipes 52 sC penetratesthrough the platy fins 52 sD. A plurality of platy fins 52 are disposedat intervals along the direction in which each of the heat transferpipes 52C extends. The platy fins 52 sD are used as plates forrectifying the airflows flowing between the heat transfer pipes 52 sC.The heat exchanger 52 sa does not necessarily include the platy fins 52sD.

The heat exchanger 52 sa causes heat exchange between the cooling waterflowing in from the flow-in piping 42 (92) and the airflow that isguided by the fan 51 sa and pass between the heat transfer pipes 52 sC,thereby cooling the cooling water. There is no limitation on the numberof heat transfer pipes 52 sC as long as multiple heat transfer pipes areused. There is no limitation also on the number of platy fins 52 sD.

FIG. 16 is a front view of the first air cooler 50 sa according to thethird embodiment. FIG. 17 is a cross-sectional view of the first aircooler 50 sa according to the third embodiment, taken along the lineB-B. As shown in FIGS. 14 and 17, the heat exchangers 52 sa 1, 52 sa 2and 52 sa 3 are set by being stacked downward in a vertical direction Xinside the cover 110 a according to the order they appear in thissentence. The heat exchangers 52 sa 4, 52 sa 5 and 52 sa 6 are set bybeing stacked downward in the vertical direction X inside the cover 110a according to the order they appear in this sentence. The heatexchangers 52 sa 1, 52 sa 2 and 52 sa 3 and the heat exchangers 52 sa 4,52 sa 5 and 52 sa 6 are disposed to be opposed to each other in thedirection of the airflow passing between the heat transfer pipes 52 sC.As shown in FIGS. 14 and 17, the air cooler 50 sa has a space 120 abetween the heat exchangers 52 sa 1, 52 sa 2 and 52 sa 3 and the heatexchangers 52 sa 4, 52 sa 5 and 52 sa 6.

As shown in FIG. 17, the fan 51 sa takes in the air in the space 12 ainside the cover 110 a and discharges the air to the outside of the aircooler 50 sa. Accordingly, the fan 51 sa causes airflows Wsa eachcirculating between the heat transfer pipes 52 sC of each of the heatexchangers 52 sa to the space 120 a. The airflows Wsa pass between theheat transfer pipes 52 sC and thus cool the cooling water in each heatexchanger 52 sa. The airflows Wsa flowing between the heat transferpipes 52 sC merge in the space 120 a and flow out of the air coolers 50sa via the fan 51 sa. In other words, the space 120 a is on the sidewhere the fan 51 sa takes air in and is positioned on the upstream sideaccording to the airflows Wsa with respect to the fan 51 sa. The heatexchangers 52 a are positioned on the upstream side according to theairflows Wsa with respect to the space 120 a.

As described above, the first air cooler 50 sa includes the heatexchanger 52 sa, the fan 51 sa that circulates the airflows Wsa betweenthe heat transfer pipes 52 sC and the space 120 a in which the airflowsWsa circulate on the upstream side according to the airflows Wsa withrespect to the fan 51 sa. Because the second air cooler 50 sb and thethird air cooler 50 sc have the same configuration as that of the firstair cooler 50 sa, descriptions thereof will be omitted. The wholestructure of the intercooler 40 s according to the third embodiment willbe described next.

FIG. 18 is a side view of the intercooler 40 s according to the thirdembodiment. FIG. 19 is a cross-sectional view of the intercooler 40 saccording to the third embodiment, taken along the line C-C. FIG. 20 isa cross-sectional view of the intercooler 40 s according to the thirdembodiment, taken along the line C-C. As shown in FIGS. 13 and 18, inthe intercooler 40 s according to the third embodiment, the first aircooler 50 sa, the second air cooler 50 sb, and the third air cooler 50sc are set adjacently according to the order they appear in thissentence in the horizontal direction Y serving as the horizontaldirection with respect to the vertical direction X. The Y direction isthe direction intersecting with the direction in which the heatexchangers 52 sa 1, 52 sa 2 and 52 sa 3 are opposed to the heatexchangers 52 sa 4, 52 sa 5 and 52 sa 6.

On a side surface 124 of the first air cooler 50 sa that is opposed tothe side surface adjacent to the second air cooler 50 sb, a wall 122that partitions the space 120 a and the outside of the intercooler 40 sis provided. Similarly, on a side surface 126 of the third air cooler 50sc that is opposed to the side surface adjacent to the second air cooler50 sb, the wall 122 that partitions space 120 c in the third air cooler50 sc and the outside of the intercooler 40 s is provided. As shown inFIG. 19, the space 120 a of the first air cooler 50 sa, space 120 b ofthe second air cooler 50 sb, and the space 120 c of the third air cooler50 sc communicate with one another, thereby forming space 120. A coolingmethod performed by the intercooler 40 s will be described next.

FIGS. 13 and 19 show the case where the fans 51 sa, 51 sb and 51 sc aredriven. The fan 51 sa causes airflows Wsa from the respective heatexchangers 52 sa (only the heat exchangers 52 sa 1, 52 sa 2 and 52 sa 3are shown in FIG. 19) toward the fan 51 sa via the space 120 a. Theairflows Wsa flows out toward the outside of the intercooler 40 s fromthe fan 51 sa. Similarly, the fan 51 sb causes airflows Wsb from therespective heat exchangers 52 sb (only the heat exchangers 52 sb 1, 52sb 2 and 52 sb 3 are shown in FIG. 19) toward the fan 51 sb via thespace 120 b. The airflows Wsb flow out toward the outside of theintercooler 40 s from the fan 51 sb. Similarly, the fan 51 sc causesairflows Wsc from the respective heat exchangers 52 sc (only the heatexchangers 52 sc 1, 52 sc 2 and 52 sc 3 are shown in FIG. 19) toward thefan 51 sc via the space 120 c. The airflows Wsc flow out toward theoutside of the intercooler 40 s from the fan 51 sc. In this manner, theairflows Wsa, Wsb and Wsc cool the cooling water in the respective heatexchangers 52 sa, 52 sb and 52 sc. The case where only the fan 51 sb isdriven will be described next.

FIG. 20 shows the case where only the fan 51 sb is driven. As shown inFIG. 20, when only the fan 51 sb is driven, the fan 51 sb causes theairflows Wsb from the heat exchangers 52 sb toward the space 120 b tocool the cooling water in the heat exchangers 52 sb. Because the fans 51sa and 51 sc are not driven, they do not cause the airflows Wsa and Wsc,respectively.

The space 120 b on the upstream side according to the airflows withrespect to the fan 51 sb, the space 120 a on the upstream side accordingto the airflows with respect to the fan 51 a, and the space 120 c on theupstream side according to the airflows with respect to the fan 51 sccommunicate with one another as the space 120. Accordingly, the fan 51sb causes airflows Wsa1 from the heat exchanger 52 sa toward the fan 51sb. The airflows Wsa1 pass through the heat exchangers 52 sa to cool thecooling water in the heat exchangers 52 sa and merge with the airflowsWsb. Similarly, the fan 51 sb causes airflows Wsc1 from the heatexchangers 52 sc toward the fan 51 sb. The airflows Wsc1 pass throughthe heat exchangers 52 sc to cool the cooling water in the heatexchangers 52 sc and merge with the airflows Wsb.

In the intercooler 40 s according to the third embodiment, the spaces120 a, 120 b and 120 c on the upstream side according to the airflowswith respect to the fans 51 sa, 51 sb and 51 sc communicate with oneanother as the space 120. Accordingly, as described above, only driving,for example, the fan 51 sb causes airflows toward all the heatexchangers of the air coolers 50 sa, 50 sb and 50 sc to cool the coolingwater in all the heat exchangers. For example, when the controller 41 isdriven by using an emergency power supply in an emergency, it isdesirable to reduce the power usage of the emergency power supply asmuch as possible. In this case, the intercooler 40 s according to thethird embodiment makes it possible to cool the cooling water in the heatexchangers by drying only one of the fans to reduce power usage.Accordingly, the intercooler 40 s according to the third embodimentmakes it possible to inhibit the heat exchange performance from loweringwhile reducing the power usage. According to the above descriptions, thefan 51 sb of the center air cooler 50 sb among the adjacent air coolersis driven; however, the fan is not limited to this. For example, drivingonly the fan 51 sa of the air cooler 50 sa, or the fan 51 sc of the aircooler 50 sc, at one end similarly makes it possible to cool the coolingwater in the heat exchangers of all the air coolers.

The intercooler 40 s according to the third embodiment includes the aircoolers. Accordingly, when maintenance is required for an air cooler,part of the air coolers can be detached from the intercooler 40 s formaintenance. Accordingly, for maintenance of an air cooler, because theintercooler 40 s is capable of cooling the cooling water depending onanother air cooler, the cooling function is not lost.

In the intercooler 40 s according to the third embodiment, the first aircooler 50 sa, the second air cooler 50 sb, and the third air cooler 50sc are set adjacently in the Y direction; however, the setting is notlimited to this. The intercooler 40 s may include, for example, two aircoolers or four or more air coolers. As long as the spaces on theupstream side with respect to the fans of the respective air coolerscommunicate with one another, it is possible to select a layout forsetting the air coolers as appropriate.

The heat exchangers according to the third embodiment are positioned onthe upstream side according to airflows with respect to the fans and ona further upstream side according to the airflows with respect to thespace 120 on the upstream side according to the airflows with respect tothe fans. Accordingly, the cooling water in the heat exchangers iscooled by the external air. For this reason, the intercooler 40 saccording to the third embodiment is capable of cooling the coolingwater in the heat exchangers efficiently, which makes it possible toinhibit the heat exchange performance from lowering. Note that, forexample, as represented in the second embodiment, the heat exchangersmay be positioned on a further downstream side according to the airflowswith respect to the fans.

Each of the air coolers 50 sa according to the third embodiment includessix heat exchangers. Because an air cooler includes a plurality of heatexchangers, it is possible to efficiently cool the cooling water,thereby inhibiting the heat exchange performance from lowering. However,the number of heat exchangers of an air cooler is not limited to this.An air cooler may include a plurality of heat exchangers or a singleexchanger.

Furthermore, in the first air cooler 50 sa according to the thirdembodiment, the heat exchangers 52 sa 1, 52 sa 2 and 52 sa 3 and theheat exchangers 52 sa 4, 52 sa 5 and 52 sa 6 are disposed to be opposedto each other in the direction in which the airflows Wsa flow betweenthe heat transfer pipes 52 sC; however the disposition is not limited tothis. For example, part of the heat exchangers, such as the heatexchanger 52 sa 1 and the heat exchanger 52 sa 4, may be disposed to beopposed to each other. Disposing part of the heat exchangers to beopposed to each other toward the direction in which the airflows Wsacirculate between the heat transfer pipes 52 sC allows efficientcirculation of the airflows Wsa. Note that the heat exchangers are notnecessarily opposed to each other and a layout of arraying heatexchangers can be selected as appropriate. Furthermore, the shape of thecover 110 a may be selected as appropriate according to the arraying ofthe heat exchangers.

Instead of the heat exchangers 52 sa, 52 sb and 52 sc according to thethird embodiment, the heat exchanger 52 according to the firstembodiment may be used. Using the heat exchanger 52 according to thefirst embodiment for the intercooler 40 s according to the thirdembodiment makes it possible to inhibit the heat exchange performancefrom lowering more preferably.

Modification

A modification of the intercooler according to the third embodiment willbe described next according to the drawings. FIG. 21 is a front view ofan intercooler 40 t according to the modification. FIG. 22 is across-sectional view of the intercooler 40 t according to themodification, taken along the line D-D. The intercooler 40 t accordingto the modification is different from the intercooler 40 s according tothe third embodiment in that the intercooler 40 t includes a partition130. Because other aspects of the structure of the intercooler 40 taccording to the modification are the same as those of the thirdembodiment, descriptions thereof will be omitted.

As shown in FIGS. 21 and 22, the intercooler 40 t includes the partition130. The partition 130 is provided between heat exchangers opposed toeach other in the first air cooler 50 sa, the second air cooler 50 sband the third air cooler 50 sc. For example, when a strong wind occursdue to, for example, a typhoon, the airflows flowing in from the outsidetoward the heat exchangers 52 sc 1, 52 sc 2 and 52 sc 3 may directlyflow toward the opposed heat exchangers 52 sc 4, 52 sc 5 and 52 sc 6 andflow out to the outside. In this case, the airflows having passedthrough the heat exchangers 52 sc 1, 52 sc 2 and 52 sc 3 and having beensubjected to heat exchange circulate to the heat exchangers 52 sc 4, 52sc 5 and 52 sc 6. The airflows inhibit the flow of the airflows from theoutside toward the heat exchangers 52 sc 4, 52 sc 5 and 52 sc 6. Whenthe partition 130 is provided, as shown in FIG. 22, the partition 130inhibits airflows Wsc2 flowing in toward the heat exchangers 52 sc 1, 52sc 2 and 52 sc 3 from flowing toward the opposed heat exchangers 52 sc4, 52 sc 5 and 52 sc 6. Accordingly, the intercooler 40 t according tothe modification makes it possible to inhibit the airflows Wsc2 afterbeing subjected to heat exchange from flowing into the heat exchangers52 sc 4, 52 sc 5 and 52 sc 6. The intercooler 40 t according to themodification does not inhibit the flow of airflows Wsc3 from the outsidetoward the heat exchangers 52 sc 4, 52 sc 5 and 52 sc 6. Accordingly,the intercooler 40 t according to the modification is capable of coolingthe cooling water in the heat exchangers more preferably, which makes itpossible to inhibit the het exchange performance from lowering.

The first, second and third embodiments and the modification have beendescribed. In the first, second and third embodiments and themodification, the intercooler according to the present invention coolsthe primary cooling water or the secondary cooling water; however, whatis cooled is not limited to this and other various types of equipmentmay be cooled. For example, the intercooler according to the presentinvention serves as an alternative means for cooling the cooling waterin the cooling piping 27 in the condenser 23 and is able to cool thesteam flowing from the turbine 22. Furthermore, for example, theintercooler according to the present invention is able to cool thecooling water in a spent fuel pool. The intercooler according to thepresent invention may be used as a heat pipe that cools the steam in thesteam generator 7 to liquid.

The controller 41 that controls the intercooler according to the presentinvention may be driven by an emergency power supply. For the emergencypower supply of the controller 41, such as a power generating devicedepending on natural energy, such as a wind power generator and abattery, a solar power generator and a battery, or a tidal powergenerator and a battery. Using a power generating device depending onnatural energy as the emergency power supply inhibits a power shortagein an emergency, which makes it possible to inhibit the cooling waterfrom not being cooled. For the emergency power supply, only a powergenerating device depending on natural energy may be used or, for abackup of an emergency power facility, a power generating devicedepending on natural energy may be additionally used.

The first, second and third embodiments and the modification have beendescribed; however, what is described according to the embodiments arenot to be construed to limit the embodiments. The foregoing componentsinclude ones easily conceived by those skilled in the art and onessubstantially the same, i.e., in the range of equivalency. Furthermore,the foregoing components may be combined as appropriate. Furthermore,various components can be omitted, replaced or changed within the scopeof the forgoing embodiments, etc.

REFERENCE SIGNS LIST

-   -   1 NUCLEAR FACILITY    -   4 SECONDARY COOLING SYSTEM    -   40 INTERCOOLER    -   42 FLOW-IN PIPING (CIRCULATION PIPING)    -   44 FLOW-OUT PIPING (CIRCULATION PIPING)    -   50 AIR COOLER    -   51 FAN    -   52 HEAT EXCHANGER    -   52A FIRST HEADER (HEADER)    -   52Aa, 52Ab, 52Ab, 52Ad FIRST DIVISION HEADER    -   52A SECOND HEADER (HEADER)    -   52Ba, 52Bb, 52Bb, 52Bd SECOND DIVISION HEADER    -   52C HEAT TRANSFER PIPE    -   52D PLATY FIN    -   52Da BLOCK    -   52Daa SMALL BLOCK    -   52Db DIVISION END    -   52E PARTITION    -   52F CONNECTION PIPE    -   90 INTERCOOLER    -   92 FLOW-IN PIPING (CIRCULATION PIPING)    -   94 FLOW-OUT PIPING (CIRCULATION PIPING)    -   W CIRCULATION DIRECTION

1.-15. (canceled)
 16. An air cooler comprising: a plurality of heattransfer pipes; headers to which both ends of each of the heat transferpipes that are disposed in parallel are fixed, respectively; a pluralityof platy fins through which each of the heat transfer pipes ispenetrated and that are provided at intervals in a direction in whichthe heat transfer pipes extend between the headers; and a fan thatcirculates an airflow between the platy fins, wherein the headers areformed to be sectioned into multiple rows, the heat transfer pipes aredisposed densely in a sectioned area of the headers, and the heattransfer pipes are disposed sparsely in an area between the sectionedareas of the headers, the heat transfer pipes are disposed triangularly,so that the heat transfer pipes are positioned differently between acirculation direction in which the airflow is circulated by the fan anda direction orthogonal to the circulation direction, the heat transferpipes are disposed in equilateral triangles in the sectioned area of theheaders, and the heat transfer pipes are disposed in isosceles trianglesin the area between the sectioned areas of the headers.
 17. An aircooler comprising: a plurality of heat transfer pipes; headers to whichboth ends of each of the heat transfer pipes that are disposed inparallel are fixed, respectively; a plurality of platy fins throughwhich each of the heat transfer pipes is penetrated and that areprovided at intervals in a direction in which the heat transfer pipesextend between the headers; and a fan that circulates an airflow betweenthe platy fins, wherein the headers are formed to be sectioned intomultiple rows, the heat transfer pipes are disposed densely in asectioned area of the headers, and the heat transfer pipes are disposedsparsely in an area between the sectioned areas of the headers, asection boarder is disposed in the headers in a direction intersectingwith the direction in which the airflow is circulated by the fan. 18.The air cooler according to claim 16, wherein the platy fins are formedto be divided into multiple blocks through each of which a predeterminednumber of the heat transfer pipes are penetrated, division endscorrespond to the positions of the section boarders in the headers, andthe division ends are provided to be against with each other.
 19. Theair cooler according to claim 18, wherein the platy fins that are formedto be divided into the blocks are further divided between the sectionboarders in the headers.
 20. An intercooler comprising: a circulationpiping for circulating cooling water for heat exchange using heatgenerated by a nuclear reactor of a nuclear facility; and the air cooleraccording to claim 16 that is provided to the circulation piping andthat acquires the heat of the cooling water in the circulation pipingthrough heat exchange.
 21. An intercooler, wherein in the air cooleraccording to claim 16, a space in which the airflow circulates isprovided on a side where the fan takes in air and on an upstream sideaccording to the airflow with respect to the fan, and a plurality of theair coolers are disposed to be adjacent to each other, and the spaces ofthe air coolers communicate with each other.
 22. An intercoolercomprising a plurality of air coolers that are disposed to be adjacentto each other and each of which comprises: a heat exchanger including aplurality of heat transfer pipes and headers to which both ends of eachof the heat transfer pipes that are disposed in parallel are fixed,respectively; a fan that circulates an airflow between the heat transferpipes; and a space in which the airflow circulates and that is providedon a side where the fan takes in air and on an upstream side accordingto the airflow with respect to the fan, wherein the spaces of the aircoolers communicate with each other, and the intercooler furtherincludes a controller that drives the fans, wherein the controllerdrives a part of the fans of the air coolers in one mode, and drives allof the fans of the air coolers in another mode.
 23. The intercooleraccording to claim 22, wherein the heat exchangers are provided on anupstream side according to the airflows with respect to the spaces. 24.The intercooler according to claim 22, wherein the air cooler includes aplurality of the heat exchangers.
 25. The intercooler according to claim24, wherein at least part of the heat exchangers is set to be opposed toa direction in which the airflows circulate between the heat transferpipes.
 26. The intercooler according to claim 25, wherein a partition isprovided between the heat exchangers that are provided to be opposed toeach other.
 27. The intercooler according to claim 22, wherein theheader is formed to be sectioned into multiple rows, and the heattransfer pipes are disposed densely in a sectioned area of the headerand the heat transfer pipes are disposed sparsely in an area between thesectioned areas of the headers.
 28. An intercooler comprising: acirculation piping for circulating cooling water for heat exchange usingheat generated by a nuclear reactor of a nuclear facility; and theintercooler according to claim 22 that is provided to the circulationpiping and that acquires the heat of the cooling water in thecirculation piping through heat exchange.
 29. A nuclear facilitycomprising: the air cooler according to claim
 16. 30. The intercooleraccording to claim 24, wherein at least the part of the plurality of theheat exchangers is arranged in line crossing an air flow directionbetween the heat transfer pipes.
 31. The intercooler according to claim30, wherein the header is formed to be sectioned into multiple rows, andthe heat transfer pipes are disposed densely in a sectioned area of theheader and the heat transfer pipes are disposed sparsely in an areabetween the sectioned areas of the headers.
 32. An intercoolercomprising: a circulation piping for circulating cooling water for heatexchange using heat generated by a nuclear reactor of a nuclearfacility; and the intercooler according to claim 30 that is provided tothe circulation piping and that acquires the heat of the cooling waterin the circulation piping through heat exchange.
 33. A nuclear facility(1) comprising: the intercoolers (40 s) according to claim 30.